Safety device for stamping presses and the like



March 10, 1942. E s'ANbEL 2,276,064

SAFETY DEVICE FOR STAMPING PRESSES AND THE LIKE Filed Nov. 8, 1940 2 Shets-Sheet 1 I BY Z272 Z5 564/2 (Z65. x M

March 10, 1942. E. SANDEL 2,276,064

SAFETY DEVICE FOR STAMPING PRESSES AND THE LIKE Filed-Nov. 8 1940 2 Sheets-Sheet 2 Z yi INVENTOR.

L Z W Patented Mar. 10, 1942 UNETED STATES SAFETY DEVICE FOR STAMPING PRESSES AND THE LIKE Emil Sande], St. Louis, Mo.

Application November 8, 1940, Serial No. 364,911

11 Claims. .(Cl. 74-614) This invention relates to power driven stamping presses and the like, and, has for its object the provision of a safety guard therefor disposed in front of the work space of the press, where dies and the like are positioned, to protect the operators hand and body against accidents during the descent of the press ram.

A further object of the invention resides in the provision of means for adjusting the safety guard device to meet the requirements of various sizes of stamping presses.

A further object of the invention resides in the provision of means for controlling the movement of the safety device to safety position within the first quarter revolution of the crank-shaft of the press.

With the above and other objects in view, the invention consists in the novel features of construction, arrangement and combination of parts til hereinafter more fully described and finally pointed out in the claims hereto appended.

Referring to the accompanying drawings:

Fig. 1 is a side elevation of a stamping press, or the like equipped with a safety curtain guard device embodying the features of my invention, the device being shown in full lines in non-safety or inoperative position, in dotted lines in two safety positions, and also in dotted lines in an elevated inoperative position such, as when dies are being changed, or for other purposes.

Fig. 2 is a top plan view of a press equipped with my safety device and showing the device as corresponding to the lowered full line non-safety position in Fig. 1.

Fig. 3 is a perspective view of the safety device as it appears in its safety position when the crank-shaft has turned approximately one-fourth revolution to effect initial descent of the press ram, and illustrating an operators arm and hand, which has been movedout of danger position by the device even against the operators will before the ram has fully descended.

In the drawings, I have illustrated, more or less conventionally, a power stamping press or the like designed, generally as A, and which includes suitable side frame members I and I; the operators table 2, the crank-shaft 3, and the plunger or ram 4, the reciprocating movement of which is controlled by rotation of the crankshaft 3 in the usual well known manner.

In cooperation with the press, I employ a pair of lever arms designated, generally as 5 and 5'. The lever arms 5 and 5', as illustrated, each consists of a rear socket member 6 having a bearing head 1, a rod 8, a front socket member 9 having of the shaft l'l passes. "22 encircles the shaft ll within the bore I9 and OFFICE a forward head portion Ill. The forward or free ends of the rods 8-are preferably fixedly secured to the front socket member 9.

The rear ends of the rods 8 are telescopically connected with the rear socket members 6. The

rear socket members 6 each have their wall longitudinally slit, as at H, for a suitable distance of the length thereof and they are each provided with a pair of ears I2 on opposite sides of the slits H. The ears l2 are adapted to receive suitable fastening devices such, for instance, as suitable screws l3 to clamp the rear ends of the rods 8 against longitudinal displacement within the socket members 6. This arrangement allows for the lengthening and shortening of the lever arms 5 and 5 to accommodate presses of different dimensions of operators tables from front to rear thereof.

The head portions 1 of each rear socket member B is provided with an opening l4 so that the head portions 1 can be mounted upon pivot pins l5 projecting from suitable supporting members 16, which are suitably secured to the press frame members I and I, such, for instance as by means of screws I6. The lever arms 5 and 5 project forwardly and downwardly from the pivot pins 1 5 to a point preferably, although not necessarily,

in advance of the forward edge of the operators table 2. I

A suitable cross-shaft Il connects the head portions ll) of the front socket members 9 and it is suitably held against rotation in openings [0' in said head portions.

A suitable roller guard member I8 is mounted for rotation, in either direction, on the crossshaft IT. The roller I8 is provided at one end with a longitudinal bore IQ of suitable dimensions and it is closed at its open end by means of a suitable cap member 20 which is suitably secured to the end of the roller and which is provided with an opening 2| through which one end A suitable coiled spring one end of the spring 22 is suitably anchored to the shaft ll, as at IT and the other end is suitably secured to the roller, as at 2 I A suitable flexible curtain guard 23 is suitably secured at one end thereof to the roller guard member I8 and is normally wound a number of times around the roller guardmember 18. The opposite or lower edge of the curtain guard 23, which can be of suitable heavy fabric, flexible leather, or other suitable flexible material, is provided with a suitable reinforcing member 24 having a plurality of fastener receiving openings 25.

A plurality of suitable hook shaped, or equivalent fasteners 26 are suitably secured to the front face of the press adjacent the operators table 2, and are adapted to pass through the curtain guard openings 25 to support the lower end of the guard curtain.

The means for actuating the lever arms for raising the roller guard member and stretching the guard curtain in front of the work space of the press, comprises, in part, a suitable wheel like member 21, or its equivalent, which is suittably secured to one end of the crank-shaft 3, such for instance, as by screws 28, so as to rotate therewith, a member designated, generally,

as 29, which is slidably adjustable upon one of the lever arm rods 8, and a connecting rod designated, generally, as 38.

The slidably adjustable member 29 includes a body portion 3| provided with an opening 3| through which the rod 8 of lever arm 5 passes. The wall of the body portion 3| is split, as at 32, and the wall is provided with a fastening device such, as a screw 33, for clamping the body portion 3| to the rod 6 in the desired adjusted position. Integral with the outer end of the body portion 3| is a body portion 34 having an elongated vertically disposed passage 35, and it has its lower face provided with a suitable recess 36 serving as a semi-circular bearing.

The connecting rod 38 includes a suitable L- shaped upper section 31 and a lower rod like section 38, the upper end of which is suitably connected with the lower end of the upper section 31. The upper end portion of the upper section 31 is pivoted eccentrically, as at 39, to the wheel like member 21 secured to the end of the crank shaft 3, and, the lower end portion of the rod like section 38, which is provided with screwthreads 40, passes downwardly through the paspage 35.

The lower end of the screw-threaded portion of the rod section 38 is provided with a horizontally disposed, internally screw-threaded stop member 4| to limit downwardly movement of the lever arms 5 and 5', which is normally seated in the semi-circular recessed bearing surface of the body portion 34 of the member 29 adjustably mounted on the rod 8 of the lever arm 5. The stop member 4| serves to raise the lever arms 5 and 5' and cause the roller guard member to be elevated and the guard curtain stretched to safety positions during the first quarter revolution of the crank-shaft 3, as shown in dotted lines designated, generally as B, in Fig. 1, and to final safety positions before the crank-shaft has moved one-half revolution, as shown in dotted lines designated, generally as C, in Fig. 1.

A depending chain or equivalent member 42 is carried by the press frame member I, and a suitable hook-shaped member 43 is carried by the socket member 6 of the lever arm 5. This arrangement of parts enables lever arms 5 and 5', roller guard member l8 to raise to an elevated inoperative position, designated D, as illustrated in dotted lines in Fig. 1, when it is desired to change dies, or for repairs, or for any other purpose. However, before the lever arms 5 and 5' are moved into the dotted line position designated D, in Fig. 1, the lower end of the flexible curtain guard is detached from the hooks 26 and the ends of the reinforcement member 24 will engage the lever arms 5 and 5' due to the action of the spring actuated roller l8 having a tendency to wind the curtain guard 23 upon the roller guard member I8.

Operation When the guard roller I8 is in its lowermost full line position as shown in Figs. 1 and 2, it is in its normal, or neutral position, and the ram 4 is then in its uppermost position. When the crank-shaft 3 starts to revolve, the ram 4 starts to descend, and as the crank-shaft starts to revolve, clockwise, and by the time it has moved one-quarter turn, the lever arms 5 and 5 as well as the roller guard 8 has moved to the safety position shown in dotted lines B in Fig. l, and the guard curtain 23 has been partly unwound therefrom and stretched in front of the work space on the operators table 2. As illustrated in Fig. 3, should the operator be dilatory in removing his hand from the die which he is feeding, the guard roller I8 will elevate the operators arm, and roll the same away from moving parts of the press to the safety position shown in Fig. 3, prior to the ram reaching its lowermost position and the roller guard reaching the position shown in'dotted lines designated C, in Fig. 1, which is the extreme elevated position of the lever arms and the guard roller.

It is generally assumed, and usually a fact, that safety devices designated to protect the stamping press operator handicaps the efficiency of the operation of the press to some degree, dependent upon the type of press, upright or inclinable, correctly designated dies, etc., but it has been actually found to be a fact that a press provided with my safety device will not handicap the efficiency of the operation but actually increase the efficiency thereof thereby increasing production, plus the safety feature of the device.

The many advantages of the herein described invention will readily suggest themselves to those skilled in the art to which it appertains.

From the foregoing description, it is evident that a simple device for this purpose hasbeen disclosed, but it'is to be understood that I' do not desire to restrict, or limit myself to the very details of the construction shown and described, which is merely illustrative, it being obvious that changes, not involving the exercise of invention, may be made without conflicting or departing from the spirit of the invention within the scope of the appended claims.

What I claim is:

1. In a stamping press having a crank-shaft and an operators table disposed below and in advance of the crank-shaft, a safety device of the shade roller ,type including a rotatable guard member, said member being spring actuated in one direction of rotation, a flexible curtain guard wound upon the guard member, means for anchoring one end of the curtain guard to the frame of the press adjacent the operators table, and means cooperating with the rotatable guard member and the crank-shaft operable during the first quarter revolution of the crank-shaft to elevate and simultaneously therewith rotate the guard member and thereby lengthen the flexible curtain guard between the point of anchorage thereof and the rotatable guard member and immediately in front of the Work space above the operators table.

2. In a stamping press having a crank-shaft and an operators table disposed below and in advance .of the crank-shaft, a rotatable safety guard member normally disposed adjacent the front top edge of the operators table, a flexible curtain guard cooperatingwith the guard member, pivoted members cooperating with and actuated by the crank-shaft to move the guard member upwardly and unwinding the curtain guard wound thereon to lengthen the same immediately in front of the work space above the operators table during the first quarter revolution of the crank-shaft, and said rotatable guard member being spring rotated to rewind the curtain guard upon the rotatable guard membe! and to return the member to starting position after the first half revolution of the crankshaft.

3. A safety guard for stamping presses having a crank-shaft and an operators table, cooperating guard members disposed in advance of the work space above operators table, one of the guard members being rotatable and armately elevatable, and the other guard member being flexible and windable upon and unwindable from the rotatable guard member during downward and upward movements, respectively, of the rotatable guard member, the said other guard member being anchored at it lower end to the press adjacent the front of the operators table and adapted to be stretched upwardly directly in front of the work space during upward movement of the rotatable guard member.

4. In combination with a hand feed stamping press having a crank-shaft actuated ram and an operators table, a pair of spaced lever arms pivoted at their rear ends to the frame of the press above the operators table, means for adjusting the length of the lever arms, a guard roller mounted to rotate between the free forward ends of the lever arms, said roller being spring actuated in one direction of rotation, a flexible curtain guard windable upon and unwindable from the guard roller, means for anchoring the lower end of the guard curtain to the press adjacent the forward end of the operators table, and means connecting one of the lever arms with the crank-shaft to effect upward movement of the guard roller to a safety position during the first quarter revolution of the crank-shaft and inoperative as to connection with it respective lever arm during downward movement of the lever arms.

5. A safety device for stamping presses and the like having a crank-shaft operated ram, comprising a roller like safety guard member, arcuately movable means for upwardly moving the guard member to a safety position in front of the work space of the press during one-half of the downward stroke of the ram, and means connecting the guard member with the front of the press below the work space to rotate the member during upward movement thereof to roll an operators hand outwardly from danger position, if in such a position, within the first quarter turn of the crank-shaft.

6. A safety device for stamping presses and the like having a crank-shaft operated ram, comprising a horizontally disposed cylindrical safety guard member, means for rotatably supporting the roller in front of the work space of the press, means connecting the crank-shaft with said means for moving same upwardly to a safety position in front of the work space during onehalf of the downward stroke of the ram, a flexible curtain connecting the guard member with the press in front of and below the work space to rotate the guard member in one direction during said movement of the ram and to roll an operators hand from danger position, if in such a position, during the first quarter turn of the crank-shaft, and mean for instantly returning the safety guard to neutral position'and rotate the guard member in an opposite direction just prior to completion of the first half revolution of the crank-shaft. 1

'7. In combination with a hand feed stamping press having a crank-shaft actuated ram andan operators table, of a guard member rotatably supported in advance of the operators table, "a.

guard curtain normallywound upon the guard roller, means for-anchoring the lower end of the guard curtain to the 'pressadjacent the'fr'o'nt end of the operators table, means for elevating and rotating the guard roller in one direction in front of and above the operator table during the first quarter revolution of the crank-shaft and simultaneously therewith stretching the guard curtain in front of and above the work space over the operators table, and means for rotating the guard roller in an opposite direction upon completion of the first half revolution of the crank-shaft for rewinding the guard curtain upon the guard roller and simultaneously therewith returning the guard roller to neutral position.

8. A stamping press having, in combination, a frame including an operators table, a crankshaft, and a reciprocable ram above the table with a work space between the table and the ram, a rotatable safety guard, operating means controlled by the crank-shaft during the first quarter revolution thereof to move the safety guard upwardly a, predetermined distance from a neutral position adjacent the front edge of the operators table, and means for simultaneously rotating the safety guard in a direction to roll an operators arm outwardly from the work space when contacted by the safety guard, and means for instantly lowering the safety guard and simultaneously rotating the same in an opposite direction at the completion of one-half revolution of the crank-shaft.

9. A stamping press including an operators table and a reciprocable ram, a safety guard member normally disposed adjacent the front edge of the table, operating means to move the guard member upwardly a predetermined distance during the first-half of the down stroke of the ram, means cooperating with the guard member to rotate the guard member in a direction to roll an operators arm out of the danger zone above the operators table should it be contacted by the guard member, and means for returning the guard member to neutral position after the full down stroke of the ram and rotating the guard member in a direction opposite to the first mentioned direction.

10. A stamping press having, in combination, a press frame including an operators table, a crank-shaft, a ram actuated by the crank-shaft, a pair of longitudinally adjustable lever arms, means for pivotally connecting the rear ends of said arms to the side of the press frame a predetermined distance abovethe operators table and to the rear thereof, a member connecting one of g the lever arms with the crank-shaft, said member having an eccentric connection with the crank-shaft, a guard roller mounted for rotation between the forward ends of the lever arms, a guard curtain connecting the guard roller with the forward end of the press adjacent the operators table, said guard roller being rotated clockwise upon upward movement of the lever arms, means for rotating the guard roller anti-clockwise and returning the roller and the lever arms to neutral position independent of the member connecting the said one lever arm with the crank-shaft.

11. The method of protecting a stamping press operator from accidental injury to the feeding hand and to the body from flying pieces by elevating and rolling the operator's arm out of the danger zone, which comprises raising a rotatable guard member and simultaneously therewith unrolling and stretching a curtain guard immediately in front of the work space of the press during the first quarter revolution of the crank-shaft of the press to elevate the operators arm if struck by the guard member and progressively thereafter roll the operator arm away from the work space, completing the upward movement of the guard member before the first one-half revolution of the crank-shaft, and instantly returning the guard member to starting position and simultaneously therewith rewinding the curtain guard independently of further movement of the 1 crank-shaft.

EMIL SANDEL. 

